My Emerald zoysia is thick and plush in areas, but thin and hard as a rock in others. For example, I can stick my finger down about 2.5" in a given spot and then right next to it maybe less than 1/4" because it's so hard and compacted. It's like this throughout the entire lawn; not just in a couple of isolated patches. How do I get it more uniform? Before I layed the sod 5 years ago, I put down topsoil over the newly-graded Georgia clay and even rolled the sod afterward, but there are still so many bumpy hard spots. I'm about to purchase a reel mower, so I can keep it cut a little shorter. How often do you aerate Emerald and when? I'm in Atlanta by the way. The compacted areas are so hard, it seems like topdressing would just cover up the grass completely Someone please tell me what to do to get a very even, thick, plush lawn. Thanks!